Abstract [en]

This paper discusses adaptive spatial wavelets for the class of motion-compensated orthogonal video transforms. Motion-compensated orthogonal transforms (MCOT) are temporal transforms for video sequences that maintain orthonormality while permitting flexible motion compensation. Orthogonality is maintained for arbitrary integer-pixel or sub-pixel motion compensation by cascading a sequence of incremental orthogonal transforms and updating so-called scale counters for each pixel. The energy of the input pictures is accumulated in a temporal low-band while the temporal high-bands are zero if the input pictures are identical after motion compensation. For efficient coding, the temporal subbands should be further spatially decomposed to exploit the spatial correlation within each temporal subband. In this paper, we discuss adaptive spatial wavelets that maintain the orthogonal representation of the temporal transforms. Similar to the temporal transforms, they update scale counters for efficient energy concentration. The type-1 adaptive wavelet is a Haar-like wavelet. The type-2 considers three pixels at a time and achieves better energy compaction than the type-1.